Automatic transmissions and other vehicular fluid system components frequently require servicing such as replacing used fluid with fresh fluid in order to properly maintain them and extend the life of the component and associated vehicle. Early attempts at developing automatic transmission fluid transfer machines often resulted in relatively lengthy and complicated procedures. Many of these early devices required significant manual operation and supervision as the operator had to continually monitor gauges and other instruments to monitor the fluid flow to achieve the desired performance.
Recently there have been numerous advances in the field of fluid exchange machines. U.S. Pat. No. 7,111,650 to Few, assigned to the assignee of the present application, discloses a radiator fluid exchanging apparatus that includes a fresh fluid supply tank, and used fluid supply tank, pumps, and fluid lines for exchanging the old fluid and replacing it with new transmission fluid. The '650 Patent is fully incorporated herein by reference. The general mechanics of replacing fluid in a transmission is well known in the art and is substantially set forth in the cited reference, and a discussion of the plumbing of the fluid exchange machine is unnecessary to the understanding of the present invention. Only the details of the operation of the machine necessary for an understanding of the present invention is provided here.
Many of the prior art fluid exchange machines were satisfactory for efficiently replacing the transmission fluid. However, those using the machines on a daily basis constantly look to ways to automate the procedure and make the operation more streamline. For example, a processor was added to these machines to control the fluid exchange operation, monitoring the pumps and fluid levels to promote a fluid exchange where the fluid added to the system was approximately equal to the fluid taken from the system. This is important when the fluid exchange occurs while the vehicle engine is running, ensuring that adequate cooling fluid is present at all times and that the engine will not overheat. While many of these devices have also proven satisfactory in their performance there remains a need for the operator to have more control over the fluid exchange operation and to be able to control the operation to a higher degree than prior machines. The ability to control the fluid exchange relies on the user having as much information as possible in an easy to understand manner. The present invention is an advance in vehicle fluid exchange machines that incorporates greater feedback from the machine in a textual or graphical output, and thus allows the user to have more control over the fluid exchange operation.